Clamp for joining tubular bodies

ABSTRACT

A band clamp used to connect tubular bodies such as vehicle exhaust system components. The band clamp has a band extending from a first end to a second end and includes a pair of spaced ribs extending at least part way between the first and second ends. A tightening mechanism is connected to the band and includes two clamp members movable toward and away from each other for tightening and loosening of the band. The band clamp further includes a gasket located on an inner surface of the band between the ribs and extending between the first and second ends. The use of the ribs with the interposed gasket provides a mechanical interlock of the band clamp with the tubular bodies while providing a hermetic seal at the junction between the two bodies.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of U.S. Provisional PatentApplication No. 60/302,220, filed Jun. 29, 2001, and is acontinuation-in-part of U.S. patent application Ser. No. 09/886,793,filed Jun. 21, 2001, now U.S. Pat. No. 6,758,501, which itself claimspriority of U.S. Provisional Patent Application No. 60/213,791, filedJun. 23, 2000.

TECHNICAL FIELD

This invention relates to band clamps and more particularly it relatesto band clamps for joining tubular bodies.

BACKGROUND OF THE INVENTION

There are many applications in industry which require the joining of twotubular bodies such as pipes, canisters and the like for containingfluid under pressure. Many of these applications require a joint whichcan be readily opened or disassembled for purposes of maintenance orrepair. An example is that of vehicle engine exhaust systems whereinseveral different exhaust system components such as mufflers, catalyticconverters, particulate filters and pipes are coupled together fordischarging the exhaust gases to the atmosphere. In exhaust systems, thetypical components are round or roundish in cross-section and the jointsmust provide a good fluid seal against exhaust gas leakage. Also, thejoints must exhibit a high degree of mechanical strength forwithstanding road shock and vibration without loosening and withoutimpairment of the sealing properties of the joint.

In some applications, a joint must be provided between components whichare substantially larger in girth than that of the pipes which aretypically used between components such as mufflers and catalyticconverters. This may involve either lap joints or butt joints, either ofwhich may utilize circumferential ribs or beads to provide a positivemechanical engagement of the coupler with the components being joined.For configurations such as this where a rib or bead is used, variousband clamp arrangements have been proposed. V-band clamps are wellknown, and different examples of these are shown in U.S. Pat. No.2,731,280 to Goodliffe et al., U.S. Pat. No. 5,411,162 to Koziczkowskiet al., and U.S. Pat. No. 6,073,977 to Schmidt-Hansen et al. As shown inthe last of these, a rubber seal can be included that spans the twobeads. Band straps having spaced circumferential ribs are also known foruse in connecting sheet metal pipes. See U.S. Pat. No. 3,207,538 toPattillo. The draw band disclosed therein comprises an open loop inwhich the ends overlap each other when the band is tightened. Such anarrangement results in a discontinuous step at the inner terminal end ofthe band and can be problematic for applications where a strong hermeticseal is needed such as in vehicle exhaust systems. This can be true evenwhere a gasket is provided since the gasket is not subjected to uniforminwardly radial pressure at the inner terminal end of the band.

Therefore, it is a general objective of this invention to provide animproved band clamp which overcomes certain disadvantages of the priorart.

SUMMARY OF THE INVENTION

In accordance with this invention, a band clamp is provided for making ajoint between tubular bodies which exhibits high pull-apart strength andalso provides a good seal against fluid leakage. The band clamp includesa band extending from a first end to a second end and including a pairof spaced ribs extending at least part way between the first and secondends. A tightening mechanism is connected to the band and includes twoclamp members movable toward and away from each other for tightening andloosening of the band. The band clamp further includes a gasket locatedon an inner surface of the band between the ribs and extending betweenthe first and second ends. The use of the ribs with the interposedgasket provides a mechanical interlock of the band clamp with thetubular bodies being joined while providing a seal against the escape offluid at the junction between the two bodies.

In accordance with another aspect of the invention, a clamping assemblyis provided which includes the band clamp, with or without a gasket,along with a pair of adapters for connecting to the tubular bodies toprovide them with suitable ribs that mate with those of the band clamp.This permits the band clamp to be retrofitted to existing tubularbodies, such as vehicle exhaust system components, that do not includeany ribs or beads at their adjoining ends.

A complete understanding of this invention may be obtained from thedetailed description that follows taken with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred exemplary embodiments of the invention will hereinafter bedescribed in conjunction with the appended drawings, wherein likedesignations denote like elements, and wherein:

FIG. 1 is a perspective view of a first embodiment of the band clamp ofthis invention;

FIG. 2 is a perspective view of two tubular bodies joined by the bandclamp of FIG. 1;

FIG. 3 is a side elevation view of the assembly as shown in FIG. 2;

FIG. 4 is an end view of the assembly as shown in FIG. 2;

FIG. 5 is a sectional view taken on lines 5—5 of FIG. 4;

FIG. 6 is a sectional view taken on lines 6—6 of FIG. 4;

FIG. 7 is an enlarged, fragmentary sectional view as in FIG. 6 showing apreassembled condition of a modification of the first embodiment thatincludes a fiberglass gasket;

FIG. 8 is sectional view as in FIG. 7 following assembly and tighteningof the band clamp with its fiberglass gasket;

FIG. 9 is a cross-sectional view of the gasket of FIGS. 7 and 8;

FIG. 10 is a sectional view as in FIG. 7 showing a pre-assembledcondition of another modification of the first embodiment that includesa graphite gasket;

FIG. 11 is sectional view as in FIG. 8 following assembly and tighteningof the band clamp with its graphite gasket;

FIG. 12 is a fragmentary, perspective view of the inside pocket andtongue portion of the first embodiment showing use of the fiberglassgasket of FIGS. 7 and 8;

FIG. 13 is an exploded view of a pair of exhaust system components andthe band clamp of FIG. 1;

FIG. 14 is a perspective view of the assembled components of FIG. 13;

FIG. 15 is a perspective view of a second embodiment of the band clampof this invention;

FIG. 16 is a reverse perspective view of the band clamp of FIG. 15showing the closing of the band and gasket during tightening of theclamp;

FIG. 17 is an exploded view of the gasket, band, and strap portions ofthe band clamp of FIG. 15;

FIG. 18 is a perspective view of a third embodiment of the band clamp ofthis invention wherein the band clamp includes inverted (concave) ribs;

FIG. 19 is a fragmentary sectional view of either of the first twoembodiments of the band clamp in a pre-assembled condition as it couldbe used with a fiberglass gasket for a lap joint between tubular bodies;

FIG. 20 is a view as in FIG. 19 following assembly and tightening of theband clamp;

FIG. 21 is a fragmentary sectional view of either of the first twoembodiments of the band clamp in a pre-assembled condition as it couldbe used with a graphite gasket for a lap joint between tubular bodies;

FIG. 22 is a view as in FIG. 21 following assembly and tightening of theband clamp;

FIG. 23 is a perspective view of a fourth embodiment of the band clampof this invention;

FIG. 24 is a side elevation view of the band clamp of FIG. 23;

FIG. 25 is an end view of the band clamp of FIG. 24;

FIG. 26 is a sectional view taken on lines 10—10 of FIG. 25;

FIG. 27 is a sectional view taken on lines 11—11 of FIG. 25; and

FIG. 28 is a side elevation view which shows two band clamps of thisinvention each of which makes a separate joint between opposite ends ofone device and the ends of two adjoining devices.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, the invention will be described indifferent embodiments of a band clamp especially adapted for making ajoint between two tubular members. The invention will be described withreference to its use in a vehicle exhaust system. In this application,the band clamp is preferably made of stainless steel with a tighteningmechanism of the type described in Cassel U.S. Pat. No. 3,905,623granted Sep. 16, 1975, the disclosure of which is hereby incorporated byreference. Other tightening mechanisms can be used such as are disclosedin Cassel U.S. Pat. No. 4,312,526 granted Jan. 26, 1982 and Cassel U.S.Pat. No. 6,269,524 granted Aug. 7, 2001, and the complete contents ofthese patents are also hereby incorporated by reference. Other, morediverse tightening mechanisms can be used as well. In this regard, itwill be appreciated as the description proceeds that the invention isuseful in many different applications and may be implemented in manyother embodiments.

The following illustrative example is applicable to retrofitting theband clamp of this invention to a catalytic converter and particulatefilter as these devices are currently manufactured by providing anadapter on each such device which will accept the band clamp of thisinvention. In particular and with reference to FIGS. 1-6, the band clampassembly is used for making a joint between a catalytic converter 1 anda particulate filter 2. The converter 1 has a cylindrical casing 3 andthe filter 2 has a cylindrical casing 4 which is substantially the samediameter as casing 3. Both casings 3 and 4, at their adjoining ends, aresubstantially the same diameter and have a plain cylindrical surface, asthey are conventionally manufactured. In order to use the band clamp ofthis invention with these conventional casings 3 and 4, it is necessaryto use an adapter member on each casing. These adapters along with theband clamp together comprise a clamping assembly that is useful inretrofit applications where the tubular bodies are not specificallymanufactured to be used with the band clamp. The band clamp of thisinvention will coact with the adapter to make a joint between the endsof the converter and the filter which will provide high pull-apartstrength and a good fluid seal against exhaust gas leakage. In order toadapt the ends of the converter 1 and filter 2 to the characteristics ofthe clamp, an adapter collar 5 on either the converter or filter and amating adapter ring 6 on the other. The adapter collar 5, as best shownin FIG. 5, comprises an annular bridging member 7 which is trough-shapein cross-section with longitudinally extending edge flanges 8 and 9. Theedge flange 8 encircles the end of the cylindrical housing 3 of theconverter and the end flange 9 encircles the end of the cylindricalhousing 4 of the filter. The end flange 8 is attached around itsperiphery to the cylindrical housing 3 by a weld 10. The edge flange 9is provided with an annular rib 11 which coacts with the band clamp in amanner to be described below. The adapter ring 6 encircles thecylindrical filter casing 4 and is attached thereto by a weld 12. Thering 6 is formed with an annular rib 13 which is adapted to coact withthe band clamp 20 as will be described below.

When the catalytic converter 1 and the particulate filter 2 are to bejoined together, the end of the cylindrical filter casing 4 is insertedinto the edge flange 9 of the adapter collar 5, with the opposed ends ofthe adapter ring 6 and the edge flange 9 in abutment with each other asshown in FIGS. 5 and 6. Then, the clamp band 20 is disposed around theannular ribs 11 and 13 as will be described below.

By a modification of the embodiment described above, the adapter collar5 and the adapter ring 6 are dispensed with and the annular rib 11 islocated near the end of the cylindrical casing 3 of the converter andthe annular rib 13 is provided near the end of the casing 4 of thefilter. This modification permits the joint to be made with fewer partsand with a closer coupling between the converter and the filter. Tofacilitate handling while the band clamp is applied to make a joint, theadjoining ends of the two casings may be provided with mating telescopicrings.

First Embodiment of this Invention

The first embodiment of the band clamp and clamping assembly of thisinvention will be described with reference to FIGS. 1-6. The band clamp20 comprises, in general, a clamp band 22 and a clamp tighteningmechanism 24. The band 22 comprises a clamp sleeve 26 that is formed asa roundish-shaped sector which defines a circumferential loop. The band22 has first and second ends which in this embodiment are located at apair of confronting end flanges 28 that extend radially from the bandand are unitary therewith. The end flanges 28 serve as parts of theclamp tightening mechanism 24. Each end flange 28 terminates at itsouter end in a retainer bight 32 which is formed by folding the end ofthe flange on itself to provide a double layer of sheet metal. Thesefolded end flanges 28 comprise clamping members that, when drawntogether, pull the first and second ends of the band toward each otherto thereby tighten the band clamp.

The clamp tightening mechanism 24 comprises the pair of end flanges 28,a reaction member or spline 34, bolt 36, spacer bar 48, nut 38 and awasher 42. The spline 34 has opposed sidewalls 44 which are arcuate andconcave in cross-section; it also has an inner surface 46 which isconcave in cross-section with a curvature conforming to the member itseats against when the clamp is tightened. The head of bolt 36 isdisposed adjacent one end flange 28 and has an inner surface with anarcuate cross-section corresponding to the opposed surface of the spline34. The spacer bar 48 is disposed adjacent the other end flange and hasan arcuate cross-section on its inner surface corresponding to that ofthe reaction member 24. The end flanges 28, spline 34 and spacer bar 48are provided with aligned bolt holes for receiving the shank of the bolt36 with the bolt head seated on the outside surface of one end flange 28and with the nut 38 and washer 42 seated against the outside surface ofthe other end flange 28.

The clamp band 22 is made from the single piece of sheet metal,preferably stainless steel, delimited circumferentially by the endflanges 28 and axially by a pair a lateral edges that extend between thefirst and second ends. The band 22 is provided with structural partsincluding annular ribs 52 and 54, dome-shaped pockets 56 and 58, and acentral portion 60 between the ribs 52 and 54. These elements, alongwith end flanges 28, bights 32, and bolt holes are all preferably formedby conventional metal-forming techniques with the material in a flatcondition. After the above-mentioned metal-forming operations, the clampband 22 is additionally formed into an open loop structure as best shownin FIG. 1.

The annular ribs 52 and 54 have a cross-sectional configuration which isarcuate and convex with respect to the outer surface of the sleeve 26.This cross-sectional configuration of ribs 52 and 54 conforms with thatof the ribs 11 and 13 provided in the adapter collar 5 and the adapterring 6, respectively. The ribs 52 and 54 are located inwardly of thelateral edges and are spaced from each other by a distance that permitsmating of each clamping rib 52 and 54 with its respective rib 11 and 13from one of the two adapters. The central portion 60 spans the distancebetween the clamping ribs 52 and 54 and overlies the junction betweenthe adapters 5 and 6 when the band is assembled over their adjoiningends.

As shown in FIG. 6, the mating pair of ribs 52 and 11 and the matingpair of ribs 54 and 13 both provide a good gas seal by virtue of thetight engagement which can be achieved throughout circumferential lengthof the ribs. In order to provide a good gas seal in the vicinity of theclamp tightening mechanism 24, a tongue 56 is provided which spans thegap between the end flanges 28 and overlaps a part of the clamp sleeve26 on both sides of the gap. The amount of overlap on each side of thegap is suitably about one-eighth of the circumference of the band clamp.The tongue 56, as shown in FIG. 5, is flat in the central regionextending between the peaks of the ribs 11 and 13 and is arcuate at itsfree edges with a curvature corresponding to the outboard portions ofthe ribs so as to provide close sealing engagement therewith. As shownin FIGS. 1 and 4, the clamp sleeve 26 is provided with dome-shapedpockets 62 and 64 each of which extends circumferentially from arespective end flange 28. The pockets 62 and 64 are suitably of equalcircumferential length and the length between their outer ends issufficient to accommodate the tongue 56 within the dome-shaped pockets.The tongue 56 is suitably welded at one end to the clamp sleeve 26. Theclamp sleeve has a cross-sectional configuration throughout thedome-shaped pocket 56 as shown in FIG. 5. This cross-section includes acentral region spanning the width of the tongue 56 in close conformitytherewith and terminating in opposite edges which are flat and inengagement with the flat portions of the respective adapter ring 6 andadapter collar 5. The dome-shape pocket 62 is of the same configurationas dome-shape pocket 64.

In use of the band clamp 20, it is applied in its loosely assembledcondition around either the converter 1 or the filter 2 before these twocomponents are brought together. When the converter and filter arepositioned with the edge flange 9 abutted against the adapter ring 6,the clamp band is positioned so that the annular ribs 52 and 54 aremated with the ribs 11 and 13, respectively. Then, the band clamp 24 istightened to a specified torque to achieve a final tightening of theclamp. In this condition, the clamp sleeve 26 is stretched around theannular ribs 11 and 13 and applies a clamp load which is sufficient tocause the mating ribs 11 and 52 and the mating ribs 13 and 54 to be influid tight engagement around the periphery of the ribs; further, thetongue 56 is pressed in tight sealing engagement against the ribs 11 and13 by the clamp sleeve 26 which engages at its outer edges with the flatportions of the adapter ring 6 and the edge flange 9 to form a gas tightseal.

Referring now to FIGS. 7 and 8, in a first modified form of theembodiment of FIGS. 1-6, a gasket 70 is provided at the central portion60 to further improve the sealing of the adapter collar 5 and ring 6against the escape of gas through the junction 72 formed between thesecomponents. As shown in FIG. 7, the gasket 70 is initially attached tothe band 22 at its central portion 60 by an adhesive or the like, andthis can be done as a part of the manufacturing of the band clampitself. Alternatively, the gasket 70 could be provided as a separatecomponent that is not attached to the band 22 until final assembly ofthe clamp over the components being joined. As shown, the gasket isprovided with a sufficient width to span the junction 72 and provide asignificant sealing overlap with each of the two adapters 5 and 6. Forthis purpose, the gasket 70 partially overlies the ribs; however, itdoes not entirely cover the ribs in order to provide good metal-to-metalcontact of the adapter ribs 11, 13 with the clamping ribs 52, 54. Toaccommodate the thickness of the gasket 70 and maximize thismetal-to-metal contact of the ribs, the central portion 60 of the band22 is recessed as shown at 74, with this recess extending from an innerside edge of one rib 52 across the central portion 60 to the other rib54.

Gasket 70 comprises a compressible material and any of a number ofsuitable homogenous or composite gasket materials can be used dependingupon the temperature and mechanical durability constraints required fora particular application. For example, the gasket 70 can be a fiberglassor mica gasket. In the illustrated embodiment, a fiberglass gaskethaving an aluminum outer surface is used, as shown in FIG. 9. Thisgasket 70 includes a layer of temperature resistant silica fabric 76rated for 980° C. that is aluminized. This aluminum surface 78 isoriented to face radially inwardly when the gasket is attached to theband 22 so that the aluminum surface 78 directly contacts the outersurfaces of the adapters 5 and 6.

Referring now to FIGS. 10 and 11, another modified version of the firstembodiment is shown using a graphite gasket 80 in lieu of the fiberglassgasket 70 of FIGS. 7-9. This graphite gasket can be a braided Inconel™with carbon yarn that is impregnated with graphite. Gasket 80 isinitially placed within the junction 72 between the adapters 5 and 6 andis sized to be somewhat wider than the ultimate span of the junctionwhen the band 22 is tightened over the adapters. Thus, as shown in FIG.11, tightening of the band acts to draw the adjoining end faces of theadapters toward each other, compressing the gasket 80 axially andthereby forming a hermetic seal at the junction 72. As will beunderstood by those skilled in the art, fiberglass gaskets such asgasket 70 can be compressed radially, as occurs in the assembly shown inFIGS. 7 and 8, whereas graphite gaskets such as shown in FIGS. 10 and 11work well when compressed axially.

Another difference between gaskets 70 and 80 is that the graphite gasketcomprises a closed loop that is assembled onto the assembly separatelyfrom the band 22, whereas the gasket 70 is an open loop in the form of astrip of gasket material that is discontinuous at its ends. As shown inFIG. 12, the gasket 70 extends circumferentially around the band 22starting at an edge 82 of pocket 64 and terminating at the edge 84 oftongue 56 that is adjacent the starting edge 82. Preferably, the gasket70 extends slightly beyond the end 84 of the tongue 56 so that theopposite ends of the gasket overlap each other when the band 22 is fullytightened.

FIGS. 13 and 14 depict pre-assembled and assembled views of a pair ofexhaust system components, such as a catalytic converter 1 andparticulate filter 2 each having a rib formed as a unitary portion ofthe canister housings, thereby obviating the need for the adapters 5 and6. Although this and the other embodiments shown depict the use ofcircular components, it will be appreciated that the band clamp andclamping assembly of this invention can be used with components havingother cross-sectional shapes.

Second Embodiment of this Invention

Turning now to FIGS. 15-17, a second embodiment of a band clamp of thisinvention is shown which can be used in conjunction with the adapters 5and 6 shown in FIGS. 1-6 or with components having unitary ribs, such asshown in FIGS. 13-14. Elements of this embodiment that correspondfunctionally to similar elements of the first embodiment are identifiedwith numerals offset by 100 from those used in the first embodiment.Some of these components can be constructed identically to thecorresponding components from the first embodiment such as, for example,the tightening mechanism.

Thus, band clamp 120 of FIGS. 15-17 include a band 122 and tighteningmechanism 124. Whereas the clamp members 28 of the first embodiment areunitary extensions of the band 22 itself, the clamp members 128 of thissecond embodiment are formed as confronting portions of a pair of strapsections 125 and 127 that are attached to band 122 by three spot weldseach. This enables band 122 to form a single open loop extending from afirst end 131 to a second end 133 with these ends being aligned witheach other and spaced by a gap that can be closed when the band is fullytightened. In this way, the pocket and tongue construction of the firstembodiment is eliminated and replaced by a substantially continuoussealing surface extending circumferentially all the way around the band122. The aligned ends 131 and 133 of band 122 are located at a differentangular position about the circumference of the band than the tighteningmechanism 124, so that the strap section 125 therefore overlies the gap.For this purpose, the strap section 125 is approximately twice as longas strap section 127. Both strap sections span the entire width of band122 to add mechanical strength to the overall band clamp.

The band clamp 120 is designed to have a total circumferential distanceabout its inner surface that is specific to the particular applicationfor which it is used so that it can be filly tightened when in use andwill provide a desired amount of clamping force when fully tightened. Toaccurately maintain this specific distance when attaching the strapsections 125 and 127 to the band 122, alignment notches 135 are providedin both the band 122 and each of the strap sections so that properregistration of the strap sections with the band can be maintainedduring welding.

As best seen in FIG. 16, the first and second ends 131 and 133 of theband are separated by a gap that is adjustable by tightening andloosening of the clamping mechanism 124. These first and second endsinclude complementary mating portions 137 and 139 that come intoengagement during tightening of the band 122. In the embodiment shown,these mating portions include two sets of spring members 137 in thefirst end 131 and two grooves 139 in the second end 133. Duringtightening of the band clamp 120, each pair of spring members engageopposing edges of their associated groove and are squeezed towards eachother to thereby form an interference fit with the groove. In this way,the band 122 provides a substantially continuous sealing surface aboutits circumference. The construction and use of the spring members andgrooves are more fully disclosed in U.S. patent application Ser. No.U.S. 2002/0014772 A1, the entire contents of which are herebyincorporated by reference. The spring members and grooves can be locatedat the two ribs; that is, axially aligned with the ribs.

The band clamp 120 includes a fiberglass gasket 170 as in FIGS. 7-9,although depending upon the particular application, a graphite or othergasket, or even no gasket may be used. Gasket 170 extends from the firstend 131 of the band 122 to its second end and is discontinuous at theseends. As with the first embodiment shown in FIG. 12, the gasket canextend slightly beyond one or both of the ends 131 and 133 so thatopposite ends of the gasket overlie each other when the band clamp isfully tightened.

Third Embodiment of this Invention

The third embodiment of this invention can be implemented the same as inthe first or second embodiments except for the structure of the annularribs. In the third embodiment shown in FIG. 18, the ribs 190 on the band192 of the band clamp 194 are concave in cross-section with reference tothe outer surface of the clamp sleeve instead of being convex as in thefirst two embodiments. Likewise, the annular ribs on the componentsbeing joined (such as the catalytic converter and particulate filter)are concave with respect to the outer surface. Otherwise the structureof the clamp band is the same as that of the first two embodiments ofthis invention.

The first three embodiments discussed above have involved the joining oftubular bodies or adapters having abutting ends. As shown in FIGS.19-22, the band clamp of this invention can be used for lap joints aswell. As in the first embodiments, it will be noted that, where a gasket270 or 280 is used, it is located at the junction 272 between the bodiesto thereby provide a hermetic seal.

Fourth Embodiment of this Invention

The fourth embodiment of this invention will be described with referenceto FIGS. 23-28. This embodiment is especially adapted for making a jointbetween the ends of two devices which are of substantially the samediameters with the end of each device being provided with an annularbead. As shown in FIGS. 23 and 27, the band clamp 220 is used to form afluid tight joint between one end of a filter 271 and an end of amuffler section 272 a or 272 b. As shown in FIG. 28, the filter 271 isinserted between the two sections 272 a and 272 b of the muffler.

As shown in FIGS. 24-27, the filter 271 is provided with a cylindricalcasing 273 and a circular end panel 274. The casing 273 and panel 274are joined by a mechanical interlock which forms a peripheral bead 275.The other end of the filter 271 has the same construction. The mufflersection 272 a comprises a cylindrical casing 276 and an end panel 277which are joined in an annular bead 278.

The band clamp 220 is of the same construction as the band clamp 20described above except for the cross-sectional configuration of theclamp sleeve 226. The other parts of the band clamp 220 are shown in thedrawings with the same reference numerals as used in FIGS. 1-6 exceptfor being offset by 200. In these FIGS., the clamp tightening mechanism224 includes a pair of bolts and associated hardware (not shown) insteadof a single bolt as in the first embodiment.

The clamp sleeve 226 has a U-shaped cross-section with a configurationthat matches the composite configuration of beads 275 and 278 as shown.The tongue 256, as shown in FIG. 26, has a cross-sectional configurationwhich conforms to the composite configuration of beads 275 and 278 andthe dome-shaped pockets 262 and 264 have cross-sectional configurationconforming to that of the tongue 256.

In use, the band clamp 220 is applied in a manner similar to thatdescribed above for the first embodiment. When the tightening mechanism224 is tightened to the specified torque, the clamp provides a gas tightseal and a strong mechanical connection as described with reference tothe first embodiment. A gasket such as gasket 70 can be used, if desiredor necessary for a particular application.

It will thus be apparent that there has been provided in accordance withthe present invention a band clamp and clamping assembly which achievesthe aims and advantages specified herein. It will of course beunderstood that the foregoing description is of preferred exemplaryembodiments of the invention and that the invention is not limited tothe specific embodiments shown. Various changes and, modifications willbecome apparent to those skilled in the art and all such variations andmodifications are intended to come within the scope of the appendedclaims.

1. A band clamp for connecting two tubular bodies, comprising: a bandextending from a first end to a second end and including a pair ofspaced ribs extending at least part way between said first and secondends; a tightening mechanism connected to said band and including twoclamp members movable toward and away from each other to draw said firstand second ends toward and away from each other for tightening andloosening of said band; and a gasket located on an inner surface of saidband between said ribs and extending alone the length at said bandbetween said first and second ends such that said gasket forms acomplete loop when said first and second ends are brought together usingsaid tightening mechanism, whereby said band clamp can be disposed overand tightened around abutting ends of the tubular bodies with saidgasket inhibiting the escape of fluid through the function formedbetween the abutting ends of the two tubular bodies; wherein said clampmembers comprise confronting portions of a pair of strap sections andwherein each of said strap sections is secured to an outer surface ofsaid band near a different one of said first and second ends, said bandbeing continuous between said first and second ends with said ends beingaligned with each other and spaced by a gap having a length that can bevaried by tightening or loosening said band using said tighteningmechanism.
 2. A band clamp as defined in claim 1, wherein said first andsecond ends include complementary mating portions that come intoengagement during tightening of said band.
 3. A band clamp as defined inclaim 2, wherein said first end includes at least one set of springmembers and said second end includes at least one groove aligned withsaid spring members, wherein said spring members engage opposing edgesof said groove and form an interference fit with said groove when saidband is tightened using said tightening mechanism.
 4. A band clamp asdefined in claim 1, wherein one of said strap portions traverses saidgap such that said gap is located at a different angular position aboutthe circumference of said band than said clamping members.
 5. A bandclamp as defined in claim 1, wherein said gasket comprises a strip ofcompressible material that extends from said first end to said secondend and that terminates at said ends.
 6. A band clamp as defined inclaim 1, wherein said gasket extends beyond at least one of said endssuch that opposite ends of said gasket overlap when said band istightened.
 7. A band clamp for connecting adjacent ends of a pair ofaxially-aligned tubular bodies, wherein each of the tubular bodies havean integrally formed, substantially non-compressible radially-protrudingrib extending circumferentially around the tubular body at its end, andwherein the adjacent ends of the tubular bodies define a junctionbetween an end face of one of the tubular bodies and an end face orother surface portion of the other tubular body, with the ribs beingoffset axially from each other on each side of the junction, said bandclamp comprising: a band extending from a first end to a second end anddefining a circumferential loop that can be tightened over the adjacentends of the axially-aligned tubular bodies, said band having a pair oflateral edges extending between said first and second ends and includinga pair of clamping ribs extending circumferentially along at least aportion of said loop between said first and second ends, said clampingribs being located inwardly of said lateral edges and spaced from eachother by a distance that permits mating of each clamping rib with acorresponding rib from one of the two tubular bodies when the band isassembled over the adjacent ends of the tubular bodies, said bandincluding a central portion spanning the distance between said clampingribs and overlying the junction between the tubular bodies when the bandis assembled over the adjacent ends; a tightening mechanism connected tosaid band and including two clamp members movable toward and away fromeach other for drawing said first and second ends toward and away fromeach other to thereby permit tightening and loosening of said band aboutthe adjacent ends of the tubular bodies; and a gasket located at saidcentral portion of said band and extending along the length of said bandbetween said first and second ends, said gasket being compressibleduring tightening of said band over the tubular bodies to provide a sealat the junction of the tubular bodies for preventing fluids fromescaping out of the tubular bodies through the junction.
 8. A band clampas defined in claim 7, wherein said clamp members comprise confrontingportions of a pair of strap sections and wherein each of said strapsections is secured to an outer surface of said band near a differentone of said first and second ends, said band being continuous betweensaid first and second ends with said ends being aligned with each otherand spaced by a gap having a length that can be varied by tightening orloosening said band using said tightening mechanism.
 9. A band clamp asdefined in claim 8, wherein said first and second ends includecomplementary mating portions that come into engagement duringtightening of said band.
 10. A band clamp as defined in claim 9, whereinsaid first end includes at least one set of spring members and saidsecond end includes at least one groove aligned with said springmembers, wherein said spring members engage opposing edges of saidgroove and form an interference fit with said groove when said band istightened using said tightening mechanism.
 11. A band clamp as definedin claim 8, wherein one of said strap portions traverses said gap suchthat said gap is located at a different angular position about thecircumference of said band than said clamping members.
 12. A band clampas defined in claim 8, wherein said gasket comprises a strip ofcompressible material that extends from said hut end to said second endand that terminates at said ends.
 13. A band clamp as defined in claims8, wherein said gasket extends beyond at least one of said ends suchthat opposite ends of said gasket overlap when said band is tightened.14. A band clamp as defined in claim 7, wherein said gasket comprises afiberglass gasket.
 15. A band clamp as defined in claim 14, wherein saidfiberglass gasket includes an aluminum inner surface facing radiallyinwardly.
 16. A band clamp as defined in claim 7, wherein said gasket isattached over a central portion of said band and partially overlies eachof said ribs.
 17. A band clamp as defined in claim 7, wherein saidgasket comprises a graphite gasket.
 18. A band clamp as defined in claim7, wherein said gasket comprises a mica gasket.
 19. A band clamp asdefined in claim 7, wherein said clamp members are each located at oneof said first and second ends and comprise unitary portions of saidband, said band including a pocket located at each of said first andsecond ends, and wherein said band clamp further comprises a tonguesecured to said band within the pocket located at said first end, saidtongue extending beyond said first end and into the pocket located atsaid second end, wherein said tongue provides a seating surface for saidgasket at said first and second ends, with said seating surface beingsubstantially continuous with said central portion of said band.
 20. Aband clamp as defined in claim 19, wherein each rib extendscircumferentially along said band from one of said pockets to the otherof said pockets.
 21. A band clamp as defined in claim 20, wherein saidpockets each have a depth that is greater than the depth of saidclamping ribs.
 22. A band clamp as defined in claim 19, wherein saidgasket comprises a strip of compressible material that extends from anedge of one of said pockets to an edge of said tongue that is locatedadjacent said edge of said one pocket.
 23. A band clamp as defined inclaim 19, wherein said gasket extends beyond said tongue such thatopposite ends of said strip overlap when said band is tightened.
 24. Aclamping assembly for connecting first and second tubular bodies,comprising: a first adapter having a first edge flange at one axial endand a second edge flange at a second axial end, said first edge flangebeing adapted to be secured to an outer surface of the first tubularbody and said second edge flange being adapted to be positioned over anouter surface of the second tubular body, said first adapter including afirst circumferential rib located at said second edge flange; a secondadapter having a second circumferential rib and being capable of beingsecured to an outer surface of the second tubular body such that saidsecond circumferential rib is adjacent said first circumferential rib ofsaid first adapter with said ribs overlying the second tubular body; anda band clamp comprising: a band extending from a first end to a secondend and including a pair of spaced clamping ribs extending at least partway between said first mid second ends, said clamping ribs being spacedfrom each other by a distance that permits mating of each clamping ribwith a corresponding rib from one of the two adapters when the band isassembled over adjacent axial ends of the two adapters, and a tighteningmechanism connected with said band and including two clamp membersmovable toward and away from each other to draw said first and secondends toward and away from each other for tightening and loosening ofsaid band.
 25. A clamping assembly as defined in claim 24, furthercomprising a gasket located on an inner surface of said band betweensaid ribs and extending between said first and second ends.
 26. Aclamping assembly as defined in claim 25, wherein said adjacent axialends define a junction therebetween and wherein, upon tightening of saidband, said gasket seals said junction thereby preventing fluid fromescaping through said junction.
 27. A clamping assembly defined in claim24, wherein said first adapter comprises a collar having a differentaxial cross-sectional shape than said second adapter.
 28. A band clampfor connecting two tubular bodies, comprising: a band extending from afirst end to a second end and including a pair of spaced ribs extendingat least part way between said first and second ends; a tighteningmechanism connected to said band and including two clamp members movabletoward and away from each other to draw said first and second endstoward and away from each other for tightening and loosening of saidband; and a gasket located on an inner surface of said band between saidribs and extending between said first and second ends; wherein maidclamp members comprise confronting portions of a pair of strap sectionsand wherein each of said strap sections is secured to an outer surfaceof said band near a different one of said first and second ends, saidband being continuous between said first and second ends with said endsbeing aligned with each other and spaced by a gap having a length thatcan be varied by tightening or loosening said band using said tighteningmechanism; wherein said first and second ends include complementarymating portions that come into engagement during tightening of saidband; and wherein said mating portions are axially aligned with saidribs.
 29. A band clamp for connecting two tubular bodies, comprising: aband extending from a first end to a second end and including a pair ofspaced ribs extending at least part way between said first and secondends; a tightening mechanism connected to said band and including twoclamp members movable toward and away from each other to draw said firstand second ends toward and away from each other for tightening andloosening of said band; and a gasket located on an inner surface of saidband between said ribs and extending alone the length of said bandbetween said first and second ends such that said gasket forms acomplete loop when said first and second ends are brought together usingsaid tightening mechanism, whereby said band clamp can be disposed overand tightened around abutting ends of the tubular bodies with saidgasket inhibiting the escape of fluid through the function formedbetween the abutting ends of the two tubular bodies; wherein said gasketis made of fiberglass and includes an aluminum inner surface facingradially inwardly.
 30. A band clamp for connecting adjacent ends of apair of axially-aligned tubular bodies, wherein each of the tubularbodies have a radially-protruding rib extending circumferentially aroundthe tubular body at its end, and wherein the adjacent ends of thetubular bodies define a junction between an end face of one of thetubular bodies and an end face or other surface portion of the othertubular body, with the ribs being offset axially from each other on eachside of the junction, said band clamp comprising: a band extending froma first end to a second end and defining a circumferential loop that canbe tightened over the adjacent ends of the axially-aligned tubularbodies, said band having a pair of lateral edges extending between saidfirst and second ends and including a pair of clumping ribs extendingcircumferentially along at least a portion of said loop between saidfirst and second ends, said clamping ribs being located inwardly of saidlateral edges and spaced from each other by a distance that permitsmating of each clamping rib with a corresponding rib from one of the twotubular bodies when the band is assembled over the adjacent ends of thetubular bodies, said band including a central portion spanning thedistance between said clamping ribs and overlying the junction betweenthe tubular bodies when the band is assembled over the adjacent ends; atightening mechanism connected to said band and including two clampmembers movable toward and away from each other for drawing said firstand second ends toward and away from each other to thereby permittightening and loosening of said band inborn the adjacent ends of thetubular bodies; a gasket located at said central portion of said band,said gasket being compressible during tightening of said band over thetubular bodies to provide a seal at the junction of the tubular bodiesfor preventing fluids from escaping out of the tubular bodies throughthe junction; wherein said clamp members comprise confronting portionsof a pair of strap sections and wherein each of said strap sections issecured to an outer surface of said band near a different one of saidfirst and second ends, said band being continuous between said first andsecond ends with said ends being aligned with each other and spaced by agap having a length that can be varied by tightening or loosening saidband using said tightening mechanism; wherein said first and second endsinclude complementary mating portions that come into engagement duringtightening of said band, and wherein said mating portions are axiallyaligned with said clamping ribs.